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There are many awesome reasons for collecting seeds from your garden. Besides an obvious sense of satisfaction, it’s also an easy way to shave some serious dollars off your gardening budget and preserve the tomatoes or nasturtiums your great-grandmother grew in her garden. As well, annually selecting your earliest, best-tasting, most productive, and disease resistant veggies will result in plants that are specifically adapted for your area. Flower gardeners can also play with breeding by saving seed from those plants that offer improved traits like larger flowers or unique bloom colour.
Which seeds can be saved?
Before you head to the garden to start gathering seed, remember that not all seed can or should be saved. Aim to save seed from open-pollinated and heirloom plants rather than from hybrids. Hybrids are the result of a cross between two different parent plants and the seed saved from this type of plant does not typically come true to type. Not sure if your varieties are hybrid, open-pollinated, or heirlooms? Most seed catalogs make it easy for seed savers to tell the difference by listing ‘F1’ (hybrid), ‘OP’ (open-pollinated) or ‘heirloom’ beside each variety.
It’s also important to remember that plants can be pollinated in different ways. Certain plants are self-pollinating, while others are cross-pollinated by insects or wind. For beginners, the seeds of self-pollinated plants like peas, beans, lettuce, peppers, and tomatoes are the easiest to save. This is because you can be fairly sure that your seed will produce plants that look like their parents.
Sometimes cross pollination is a good thing and can lead to unusual flower colours when pollen is moved from one plant to another. Instead of yellow flowering nasturtiums, you may end up with salmon or deep red blooms. But, if you have a cross-pollinating plant and wish to save the seeds, you’ll need to grow just that one variety (only that yellow nasturtium, for example), or isolate related crops from each other with a barrier or plenty of space.
Want more information? There are a lot of fantastic books on seed saving like The Complete Guide to Saving Seeds and the classic Seed to Seed. And, I’m also a huge fan of the excellent book Plant Breeding for the Home Gardener by Joseph Tychonievich. It’s a comprehensive, yet easily understandable guide for anyone interested in experimenting in their veggie and flower gardens.
Collecting seeds from your garden
For me, seed collecting often begins long before the seedpods or fruits have matured. Of course, you can gather the seed from nasturtiums, marigolds, poppies, cosmos, beans, peas, and tomatoes by collecting it when the seed is ready. But, savvy seed savers who want to improve their existing plants or cultivate something new, keep their eyes open for exceptional plants throughout the growing season.
What’s an exceptional plant? With flowers, I look for unusual or better bloom colour, larger (or maybe smaller) flowers, improved disease resistance, or plants that are more robust than usual. For vegetables, I want plants that crop earlier, don’t bolt in summer, have cold tolerance, larger yields, disease resistance, or better tasting fruits. Any plants that have potential are marked with plastic bread tags, labelled twist ties, or colored yarn so that I remember which ones have been selected for seed saving.
When the fruits have reached the proper stage of maturity it’s time to start collecting seeds. Seeds are collected ‘wet’ or ‘dry’. The seeds from cucumbers, tomatoes, squash, and melons are gathered when they are wet and the fruit is over-ripe. Depending on the species, they will need a quick water rinse or a brief fermenting before the seeds can be dried and stored. Dry seeds, on the other hand, come from plants that form seedpods. These plants include poppies, beans, peas, calendula, marigolds, dill, and coriander.
Gather dry seeds when the weather is sunny and dry. If there has been rain, wait a few days for the seedpods to dry before collecting seeds from your garden. Get started by grabbing a sharp pair of garden pruners, a waterproof marker, and a pile of paper bags. Use the pruners to clip dried seedpods or capsules from the plant, dropping them in labeled paper bags.
Hang the bags in a cool, airy location to let the seedpods finish drying. Or, spread the seeds on screens to dry. When you are ready to remove the seed from the fruits, gently open the pods and pour or shake the seeds onto a piece of white paper. Bits of the dried plant, known as chaff will likely mix in with the seed. Chaff can be removed by hand or with the use of a sieve. However, as long as it’s dry and mold-free chaff shouldn’t pose a problem.
Once the seeds are ready to store, place them in small envelopes or plastic film canisters. You can find a variety of small envelopes online, some specifically for seed storing, others just plain envelopes. Seal well, label with the species, variety, and collection date and place in an airtight container such as a large glass jar or plastic storage container. Store seeds in a cool, dry place.
‘Wet’ seeds, like those from tomatoes, cucumbers, squash, and eggplants are collected from ripe fruits. For certain vegetables like squash and eggplants, the seed can be simply scooped into a bowl, rinsed clean with water, and spread to dry. But other crops, like tomatoes and cucumbers, benefit from a short period of fermentation.
To ferment seeds, place the pulp and seeds in a plastic or glass container and add water to cover. Top with a piece of plastic wrap or a plastic cover and leave for 3-4 days. Once the mixture becomes moldy, pour off the mold, rinse well with clean water, and drain and spread the seeds on newspapers or plates for 7 to 10 days or until completely dry.
Once the ‘wet’ seeds have been collected, cleaned and dried, store them the same way as dry-collected seeds; in envelopes, film canisters, jars, or plastic containers. You can also add packets of silica gel or a few spoonfuls of uncooked rice into the containers where you store your seed envelopes. These will absorb moisture and prolong storage and germination life.
Will you be collecting seeds from your garden this summer and autumn?